CN115919515B - Intervertebral prosthesis - Google Patents
Intervertebral prosthesis Download PDFInfo
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- CN115919515B CN115919515B CN202310237426.8A CN202310237426A CN115919515B CN 115919515 B CN115919515 B CN 115919515B CN 202310237426 A CN202310237426 A CN 202310237426A CN 115919515 B CN115919515 B CN 115919515B
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Abstract
The invention discloses an intervertebral prosthesis, comprising: an inferior prosthesis; an upper prosthesis; an adjustment mechanism interposed between the upper prosthesis and the lower prosthesis; the adjusting mechanism comprises: the two fixed accommodating parts are symmetrically arranged on the lower prosthesis; the movable accommodating parts face the two fixed accommodating parts respectively; a driving mechanism for driving the movable housing part to move toward the fixed housing part or away from the fixed housing part; a first stacked assembly disposed in the fixed receiving portion, the first stacked assembly including a plurality of wedge-shaped sheets stacked one on another; a second stacked assembly disposed in the movable housing, the second stacked assembly including a plurality of wedge-shaped sheets stacked one on another; the wedge-shaped sheets of the second stack and the first stack are inserted into the gaps between sheets of each other, and the driving mechanism drives the movable accommodating part to adjust the depth of the inserted wedge-shaped sheets between sheets for adjusting the height formed by the stacked wedge-shaped sheets, and the upper prosthesis is adapted to the height change of the stacked wedge-shaped sheets.
Description
Technical Field
The present invention relates to an instrument for treating intervertebral collapse, and more particularly to a prosthesis for implantation between vertebrae.
Background
The treatment effect on serious intervertebral collapse is limited by means of medicine, traction, active (or passive) exercise and the like, and the treatment effect on intervertebral collapse is remarkable by implanting collapsed vertebrae with a prosthesis for restoring the physiological distance between vertebrae.
Conventional prostheses are solid structures with non-adjustable height (or thickness) and, after implantation of the prosthesis between two vertebrae, the distance between the two vertebrae reaches the final physiological distance. However, such a prosthesis is only suitable for implantation in cases where the intervertebral collapse is light and the physiological distance is directly obtained without having to make multiple adjustments.
However, if the inter-vertebral collapse is severe, the pre-operative intervertebral distance is much smaller than the target physiological distance, and the above-mentioned conventional prosthesis is not suitable because: 1. because the distance between vertebrae before operation is smaller, the prosthesis corresponding to the target physiological distance is difficult to implant between vertebrae with smaller distance, so that the operation is difficult; 2. even if the prosthesis can be implanted between vertebrae, however, due to the abrupt increase in the inter-vertebral distance during surgery, it may not only cause damage to surrounding tissue (e.g., stretch damage) but also affect other vertebrae (e.g., abruptly change the spacing, morphology of other vertebrae).
To overcome these problems, there is provided a prosthesis capable of height (thickness) adjustment by which the prosthesis can be smoothly implanted between vertebrae at a small height at the time of operation and then gradually increasing the distance between vertebrae to finally obtain a physiological distance between vertebrae. In particular, the prosthesis generally comprises: an upper prosthesis, a lower prosthesis, and an adjustment mechanism interposed between the upper prosthesis and the lower prosthesis; the upper prosthesis is used for being fused with the upper vertebrae, the lower prosthesis is used for being fused with the lower prosthesis, and the adjusting mechanism is used for adjusting the distance between the upper prosthesis and the lower prosthesis, so that the adjustment of the vertebral distance is realized.
The prior art adjustment mechanisms for adjusting the distance between the superior and inferior prostheses generally take the following two forms:
a first form of adjustment mechanism: the adjusting mechanism comprises two sliding blocks with inclined planes which are arranged up and down, and the upper prosthesis and the lower prosthesis are driven to approach or separate by driving the two sliding blocks to move relatively and by matching the two inclined planes. However, this type of adjustment mechanism is not stable for supporting two prostheses because it uses only two inclined surfaces for cooperation, and is not suitable for fine adjustment of the upper and lower prostheses because the distance between the two prostheses is greatly changed by driving the slider by a screw drive per unit angle of screwing.
A second form of adjustment mechanism: the adjusting mechanism comprises a plurality of groups of connecting rods which are directly connected between the upper prosthesis and the lower prosthesis, and the distance between the upper prosthesis and the lower prosthesis is adjusted by twisting the driving connecting rods. However, this approach results in some degrees of freedom of the superior and/or inferior prosthesis being limited, which in turn results in the prosthesis not being able to adapt to the micro motion of the vertebrae, i.e. not providing conditions for constructing a joint-like structure between the superior and inferior prosthesis.
Disclosure of Invention
In view of the foregoing technical problems in the prior art, embodiments of the present invention provide an intervertebral prosthesis.
In order to solve the technical problems, the technical scheme adopted by the embodiment of the invention is as follows:
an intervertebral prosthesis, comprising:
a lower prosthesis, the base of which is for fusion with the lower vertebrae;
an upper prosthesis, the top of which is for fusion with an upper vertebra;
an adjustment mechanism interposed between the upper prosthesis and the lower prosthesis;
the adjustment mechanism includes:
the fixing and accommodating parts comprise two fixing and accommodating parts which are symmetrically arranged on the lower prosthesis and are fixed with the lower prosthesis;
the movable containing parts are positioned between the two fixed containing parts and are symmetrically arranged, and the two movable containing parts face the two fixed containing parts respectively;
the driving mechanism is used for driving the two movable containing parts to synchronously and correspondingly move towards the two fixed containing parts or away from the fixed containing parts;
a first stacked assembly disposed in the fixed housing, the first stacked assembly including a plurality of wedge-shaped pieces stacked one on another with thin ends of the plurality of wedge-shaped pieces facing the movable housing;
a second stacked assembly disposed in the movable housing, the second stacked assembly including a plurality of wedge-shaped pieces stacked one on another with thin ends of the plurality of wedge-shaped pieces facing the fixed housing; wherein:
the wedge-shaped sheets of the second stacked assembly and the wedge-shaped sheets of the first stacked assembly are inserted into gaps among sheets of each other, the driving mechanism drives the movable accommodating part to adjust the depth of the inserted wedge-shaped sheets among the sheets for adjusting the height formed by the stacked wedge-shaped sheets, and the upper prosthesis is adapted to the height change of the stacked wedge-shaped sheets.
Preferably, a support member is provided between the uppermost wedge-shaped plate and the lower prosthesis; the supporting part is provided with side wings formed on two sides and a spherical surface part which is positioned in the middle and protrudes upwards; the two side wings of the supporting part are respectively lapped on the wedge-shaped sheets at the two sides, and the spherical surface part is used for being matched with the middle part of the upper prosthesis.
Preferably, the method comprises the steps of,
the driving mechanism includes:
the first wedge-shaped blocks comprise two first wedge-shaped blocks which are symmetrically formed on the two movable accommodating parts respectively;
a second wedge block located between the two first wedge blocks, the second wedge block comprising a front second wedge block and a rear second wedge block; the front second wedge block and the rear second wedge block are matched with the inclined planes of the first wedge blocks at two sides and are in sliding connection with the dovetail guide strip through the dovetail groove;
the screw rod penetrates through the front second wedge block and the rear second wedge block to form threaded transmission, a force application part is formed at the end part of the screw rod, and the screw rod is screwed by the force application part to enable the front second wedge block and the rear second wedge block to be close to or far away from each other so as to drive the two first wedge blocks and the movable accommodating part to be far away from or close to each other;
a mandrel is arranged in the middle of the lower prosthesis, and the upper part of the mandrel passes through the center of the supporting part; the mandrel is provided with a step part, a spring is sleeved on the mandrel, and the spring is arranged between the step part and the supporting part; the screw rod radially penetrates through the bottom of the mandrel.
Preferably, the intervertebral prosthesis further comprises a positioning component; slots are formed in the corresponding positions of the front side of the upper prosthesis and the front side of the lower prosthesis; the positioning component comprises a plug-in part which is matched with the slots of the upper prosthesis and the lower prosthesis respectively and a connecting part which is used for connecting the two plug-in parts; the positioning component is inserted into the slot through the inserting part to position the upper prosthesis and the lower prosthesis; the outside of the positioning component is provided with an operation hole which is suitable for clamping an implantation operation workpiece.
Preferably, a wave plate is provided between the flanks of the support members and the uppermost wedge-shaped sheet.
Preferably, the method comprises the steps of,
a first guide column is arranged in the fixed accommodating part; the wedge-shaped sheet of the first stacked assembly is provided with a guide hole, and the first guide column penetrates through the guide hole of the wedge-shaped sheet of the first stacked assembly;
a second guide column is arranged in the movable accommodating part; the wedge-shaped sheet of the second stacked assembly is provided with a guide hole, and the second guide column penetrates through the guide hole of the wedge-shaped sheet of the second stacked assembly.
Preferably, the fixed accommodating part is provided with two opposite inner side walls; the first stack being defined between two of the inner side walls; the movable housing having two opposing outer side walls, the second stack being defined between the two outer side walls; wherein:
the two outer side walls are correspondingly positioned outside the two inner side walls; the outer side wall and the inner side wall form sliding fit with the sliding groove through a sliding strip.
Preferably, both sides of the thick end of each wedge-shaped piece are provided with semicircular parts protruding outwards; the cavity walls in the fixed accommodating part and the movable accommodating part are respectively provided with a semicircular groove matched with the semicircular part.
Preferably, two of the fixed accommodating parts are provided with limiting covers; the middle part of the limit cover is provided with a hollowed-out part; the spherical surface part of the supporting part penetrates through the hollowed-out part.
Preferably, the positioning member comprises two symmetrically arranged.
Compared with the prior art, the intervertebral prosthesis provided by the embodiment of the invention has the beneficial effects that:
1. the wedge-shaped sheets of the two stacked assemblies have a friction self-locking function after being inserted between the sheets, so that the stacked assemblies can be stably maintained at the adjusted height, thereby enabling the intervertebral prosthesis to be stably maintained at the adjusted thickness.
2. The slope of the inclined plane of the wedge-shaped sheet is smaller, so that the distance that the wedge-shaped sheet and the movable containing part need to move per unit height is larger, and the angle that the screw needs to be screwed is larger, and therefore, the intervertebral prosthesis provided by the invention is more suitable for fine adjustment of the intervertebral space.
3. The cooperation of the mandrel, the spring and the supporting component enables the intervertebral prosthesis to always keep the trend of increasing thickness, so that the intervertebral prosthesis can continuously expand the upper vertebrae, the expansion process is slower, the influence on other vertebrae can be reduced, and preparation can be made for the next active adjustment.
4. The wedge blocks are connected in a sliding mode through a dovetail structure, so that reciprocating linkage can be formed between the wedge blocks, and the thickness of the intervertebral prosthesis can be adjusted from large to small.
Drawings
Fig. 1 is a front view of an intervertebral prosthesis provided according to an embodiment of the present invention.
Fig. 2 is a cross-sectional view taken along A-A of fig. 1.
Fig. 3 is a B-B cross-sectional view of fig. 2.
Fig. 4 is a view showing a state in which an intervertebral prosthesis is implanted between vertebrae and before adjustment according to an embodiment of the present invention.
Fig. 5 is a view showing an intervertebral prosthetic according to an embodiment of the present invention implanted between vertebrae and after adjustment.
In the figure:
10-superior prosthesis; 20-an inferior prosthesis; 30-a junction; 21-a containing groove; 41-fixing the accommodating part; 411-inner side wall; 412-a chute; 413-a first guide post; 42-a movable housing; 421-outer side wall; 422-slide bar; 423-a second guide post; 43-a support member; 431-spherical section; 432-side wings; 44-mandrel; 441-springs; 442-retainer ring; 45-wave plate; 46-a limit cover; 51-a first stack; 52-a second stack; 60-wedge-shaped pieces; 61-thin end; 62-thick end; 63-semicircle part; 631-a semicircular groove; 70-a driving mechanism; 71-a first wedge; 721-rear second wedge; 722-a front second wedge; 731-a dovetail groove; 732-dovetail guide bar; 74-screw; 741-a force application section; 751-dovetail slots; 752-dovetail rail; 80-positioning a component; 81-plug-in parts; 82-a connection; 83-jack; 84-slots; 100-upper vertebrae; 200-lower vertebrae.
Detailed Description
The present invention will be described in detail below with reference to the drawings and detailed description to enable those skilled in the art to better understand the technical scheme of the present invention.
As shown in fig. 1 to 3, an embodiment of the present invention discloses an intervertebral prosthesis for implantation between collapsed vertebrae in order to obtain a reasonable physiological distance between the two vertebrae. The intervertebral prosthesis includes an upper prosthesis 10, a lower prosthesis 20, and an adjustment mechanism. The components involved in the superior and inferior prostheses 10, 20 and the adjustment mechanism may be made of metal, ceramic, non-metallic polymers, for example, the superior and inferior prostheses 10, 20 may be made of titanium alloys.
The top surface of the superior prosthesis 10 and the top surface of the inferior prosthesis 20 are provided with a juncture 30 that facilitates fusion with the vertebrae, for example, the juncture 30 may be provided in a surface-distributed taper angle configuration as shown in fig. 1, although it may be provided in a honeycomb configuration that facilitates ingrowth of the vertebrae, etc. As will be readily appreciated, the superior prosthesis 10 is positioned above the inferior prosthesis 20, and after implantation of the intervertebral prosthesis between the vertebrae, the superior vertebra 100 eventually merges with the top of the superior prosthesis 10 and the inferior vertebra 200 eventually merges with the bottom of the inferior prosthesis 20.
An adjustment mechanism is provided between the upper prosthesis 10 and the lower prosthesis 20 for adjusting the distance between the upper prosthesis 10 and the lower prosthesis 20, thereby enabling the distance between the two vertebrae to finally reach a physiological distance by increasing the distance between the upper prosthesis 10 and the lower prosthesis 20. To reduce the gap between the edges of the superior prosthesis 10 and the inferior prosthesis 20 so that the entire intervertebral prosthesis is more compact, a concave receiving groove 21 is provided inside the inferior prosthesis 20 so that the relevant components of the adjustment mechanism are at least partially submerged in the receiving groove 21, thus also reducing the exposed area of the adjustment mechanism.
The adjusting mechanism comprises: a fixed housing 41, a movable housing 42, a first stack 51, a second stack 52, a support member 43, a driving mechanism 70, and the like.
The fixing housing portion 41 includes two fixing housing portions 41 symmetrically arranged on both sides in the left-right direction of the lower prosthesis 20, and the bottom of the fixing housing portion 41 is integrally formed with the groove bottom of the housing groove 21, that is, the fixing housing portion 41 is integrally formed with the lower prosthesis 20. The fixed receiving portion 41 has a vertically extending rectangular guide chamber, an upper end of which is open, and which has a notch which faces inward (toward the movable receiving portion 42) and can be inserted.
The movable housing portions 42 include two, the two movable housing portions 42 are located between the two fixed housing portions 41, and the two movable housing portions 42 are symmetrically arranged, and the movable housing portions 42 are not connected with the lower prosthesis 20 and the upper prosthesis 10. The movable housing portion 42 has substantially the same guide cavity as the fixed housing portion 41, and the guide cavity has a notch facing outward (toward the fixed housing portion 41), so that two notches of the two movable housing portions 42 are respectively opposed to the notches of the two fixed housing portions 41.
As shown in fig. 1 and 2, the two movable housing parts 42 are configured to slide in a direction toward the two fixed housing parts 41 or in a direction away from the two fixed housing parts 41, specifically, the movable housing parts 42 have two outer side walls 421 disposed opposite to each other, and the fixed housing parts 41 have two inner side walls 411 disposed opposite to each other; the inner side wall 411 of the fixed housing portion 41 is located between the outer side walls 421 of the movable housing portion 42, that is, the fixed housing portion 41 and the movable housing portion 42 are inserted into each other's guide cavities through the notch. The inner side wall 411 is provided with a slide groove 412 extending in the left-right direction, and the outer side wall 421 is provided with a slide bar 422 slidably engaged with the slide groove 412. In this way, the movable housing portion 42 can strictly slide in the direction of the fixed housing portion 41 or be separated from the fixed housing portion 41.
As shown in fig. 2 and 3, each of the first and second stacked assemblies 51 and 52 is formed by stacking a wedge plate 60, and the wedge plate 60 may be made of a titanium alloy material, and both inclined surfaces of the wedge plate 60 have a small slope. The wedge-shaped sheets 60 in the first stack 51 and the second stack 52 are each arranged as follows:
the thin ends 61 of all the wedge-shaped pieces 60 of each assembly are on the same side and the thick ends 62 are on the same side, such that a tapered gap is formed between the thin ends 61 of each two wedge-shaped pieces 60.
The first stacked assembly 51 is disposed in the fixed receiving cavity, the edge of the first stacked assembly 51 defined by all the wedge-shaped pieces 60 is matched with the guide cavity, and a vertical first guide post 413 is disposed in the fixed receiving cavity, the cross section of the first guide post 413 is in an oblong shape, correspondingly, a guide hole is formed in the wedge-shaped piece 60 of the first stacked assembly 51 such that the first guide post 413 penetrates the guide hole, so that the cavity wall of the guide cavity is matched with the first guide post 413 to enable the wedge-shaped piece 60 to move only in the height direction of the intervertebral prosthesis, and the movement in other directions is limited. Preferably, the two sides of the thick end 62 of each wedge 60 are formed with convex semicircular portions 63, and the cavity wall of the corresponding area of the guide cavity is formed with semicircular grooves 631 which are matched with the semicircular portions 63, thus further limiting the operation of the wedge 60 in other directions.
The second stacked assembly 52 is disposed in the movable receiving chamber, the edges of the second stacked assembly 52 defined by all the wedge-shaped pieces 60 are matched with the guide chamber, and a vertical second guide post 423 is disposed in the movable receiving chamber, the cross section of the second guide post 423 is in an oblong shape, correspondingly, a guide hole is formed in the wedge-shaped piece 60 of the second stacked assembly 52 such that the second guide post 423 penetrates the guide hole, so that the chamber wall of the guide chamber is matched with the second guide post 423 to enable the wedge-shaped piece 60 to move only in the height direction of the intervertebral prosthesis, and the movement in other directions is limited. Preferably, the two sides of the thick end 62 of each wedge 60 are formed with convex semicircular portions 63, and the cavity wall of the corresponding area of the guide cavity is formed with semicircular grooves 631 which are matched with the semicircular portions 63, thus further limiting the operation of the wedge 60 in other directions.
As shown in fig. 3, the arrangement direction of the wedge-shaped pieces 60 in the first stack 51 and the wedge-shaped pieces 60 in the second stack 52 is configured to:
such that the thin ends 61 of the wedge-shaped sheets 60 in the first stack 51 are directed towards the slots of the movable receiving portion 42 and such that the thin ends 61 of the wedge-shaped sheets 60 in the second stack 52 are directed towards the slots of the fixed receiving portion 41, i.e. the thin ends 61 of the wedge-shaped sheets 60 of the two assemblies are oppositely arranged.
Such that the thin ends 61 of the wedge-shaped sheets 60 of the first stack 51 and the thin ends 61 of the wedge-shaped sheets 60 of the second stack 52 are inserted into the inter-sheet gaps of each other. Thus, when the movable housing portion 42 is slid toward the fixed housing portion 41, the depth between the wedge-shaped pieces 60 of the two components is increased, and thus the height formed by stacking all the wedge-shaped pieces 60 is increased, and when the movable housing portion 42 is slid away from the fixed housing portion 41, the depth between the wedge-shaped pieces 60 of the two components is decreased, and thus the height formed by stacking all the wedge-shaped pieces 60 is decreased.
As shown in fig. 3, the support member 43 is interposed between the uppermost wedge-shaped sheet 60 of the stack and the superior prosthesis 10. Specifically, the supporting member 43 includes side wings 432 on both sides and a spherical portion 431 in the middle and protruding upward. The two side wings 432 of the supporting member 43 are respectively overlapped on the uppermost wedge-shaped sheets 60 of the two sides; the spherical portion 431 abuts the inner surface of the superior prosthesis 10. After the intervertebral prosthesis is implanted between the upper vertebra 100 and the lower vertebra 200, the upper vertebra 100 and the lower vertebra 200 compress the intervertebral prosthesis such that the upper prosthesis 10 contacts the spherical surface portion 431 of the support member 43 with a certain preload and the lateral wings 432 of the support member 43 contact the uppermost wedge-shaped pieces 60 with a certain preload, so that, on the one hand, the support member 43 serves to provide a supporting force for the upper prosthesis 10 and, on the other hand, the support member 43 serves to transmit a change in height of the stacked wedge-shaped pieces 60 to the upper prosthesis 10. In this manner, when the movable receiving portion 42 is slid toward the fixed receiving portion 41, the depth of the insertion of the wedge-shaped pieces 60 of the two stacked assemblies into each other increases, so that the stacked wedge-shaped pieces 60 move upward to drive the upper prosthesis 10 upward by the supporting member 43, thereby enabling an increase in the distance between the upper prosthesis 10 and the lower prosthesis 20, thereby forcing an increase in the distance between the upper vertebra 100 and the lower vertebra 200.
In yet another aspect, the spherical portion 431 cooperates with the contact of the superior prosthesis 10 to provide the superior prosthesis 10 with a degree of freedom relative to the inferior prosthesis 20 so as to simulate a real joint.
In some preferred embodiments, a wave plate 45 is provided between the side wings 432 of the support member 43 and the wedge 60, the wave plate 45 being capable of absorbing shocks from the vertebrae and transmitted to the support member 43.
In some preferred embodiments, the upper ends of the two fixed receiving portions 41 are fastened together with a limiting cover 46, the middle of the limiting cover 46 is provided with a hollowed portion, the spherical portion 431 of the supporting member 43 penetrates through the hollowed portion, and the side wings 432 are limited by the limiting cover 46, so that the supporting member 43 is separated from the lower prosthesis 20.
As shown in fig. 2 and 3, the driving mechanism 70 is located between the two movable housing chambers, and the driving mechanism 70 includes: a first wedge 71, a second wedge and a screw 74. The first wedge blocks 71 include two, and the two first wedge blocks 71 are integrally formed on the inner sides of the two movable receiving parts 42, respectively, so that symmetrical arrangement is formed; the second wedge includes a front second wedge 722 and a rear second wedge 721; the rear second wedge 721 is located between the rear sides of the two first wedges 71, the front second wedge 722 is located between the front sides of the two first wedges 71, and both sides of the front second wedge 722 and both sides of the rear second wedge 721 are simultaneously in slant fit with the first wedges 71 on both sides, and dovetail grooves 731 and dovetail guide strips 732 are formed on the matched slant surfaces, so that the second wedge and the first wedges 71 are always in a connected state. Thus, when the front second wedge 722 and the rear second wedge 721 are close, the two movable receiving parts 42 are driven to slide towards the two fixed receiving parts 41 respectively through the inclined plane fit, so that the depth of the wedge-shaped sheets 60 inserted between the sheets is increased, and the distance between the upper prosthesis 10 and the lower prosthesis 20 is increased, and when the front second wedge 722 and the rear second wedge 721 are far away, the two movable receiving parts 42 are driven to be close through the fit of the dovetail structure on the inclined plane, namely slide towards the direction away from the fixed receiving parts 41, so that the depth of the wedge-shaped sheets 60 inserted between the sheets is reduced, and the distance between the upper prosthesis 10 and the lower prosthesis 20 is reduced. Preferably, the front and rear second wedges 722, 721 are mated with the lower prosthesis 20 through dovetail slots 751 and dovetail rails 752 such that the two wedges slide on the bottom of the receiving slots 21 of the lower prosthesis 20 to avoid separation from the lower prosthesis 20.
As shown in fig. 2, the screw 74 is threaded in the front-rear direction simultaneously with the front second wedge 722 and the rear second wedge 721, and forms a screw drive with both wedges, and the screw threads mating with both wedges are in opposite directions of rotation; the urging portion 741 of the screw 74 is located on the anterior side and does not protrude from the intervertebral prosthesis. After the intervertebral prosthesis is implanted between vertebrae, the screw 74 may be screwed by an operating tool such as a screwdriver acting on the force applying portion 741. When screw 74 is screwed, screw 74 drives front second wedge 722 closer to or farther from rear second wedge 721.
It should be noted that:
the purpose of the ramp-fit between the wedge blocks in the present invention is to drive the movable receiving portion 42, rather than to directly support the upper prosthesis 10 and/or the lower prosthesis 20, and thus, unlike the prior art slider action by the ramp-fit, in which the ramp-fit slider is used to directly support the upper prosthesis 10, the wedge blocks in the present invention do not contact the upper prosthesis 10.
A mandrel 44 is arranged in the middle of the lower prosthesis 20, a screw 74 penetrates through the bottom of the mandrel 44, and the heads of the two first wedge-shaped blocks 71 form arc-shaped concave parts so as to avoid the mandrel 44; the spherical portion 431 of the support member 43 is inserted into the upper portion of the spindle 44, a stepped portion is formed in the spindle 44, a spring 441 is fitted over the upper portion of the spindle 44, the spring 441 is interposed between the spherical portion 431 and the stepped portion, and a retainer ring 442 is provided at the upper end of the spindle 44, the retainer ring 442 being for restricting the support member 43 from coming out of the upper end of the spindle 44. After the intervertebral prosthesis is implanted between the vertebrae, the compression of the upper prosthesis 10 by the vertebrae causes the spring 441 to exert a certain elastic force on the upper prosthesis 10, the function of this spring 441 being: on the one hand, the spring 441 is capable of effectively buffering the impact from the upper prosthesis 10 and the lower prosthesis 20; on the other hand, the elastic force of the spring 441 makes the upper prosthesis 10 always have a continuous pushing force on the upper vertebrae 100, and thus, without actively increasing the thickness of the intervertebral prosthesis (i.e., after the patient implants the intervertebral prosthesis, before the next active adjustment), the intervertebral prosthesis automatically and continuously slowly expands the upper vertebrae 100 in such a way as to have a small influence on other vertebrae due to the slowness and to facilitate the next active adjustment.
As shown in FIG. 1, in some preferred embodiments, slots 84 are provided in corresponding areas of the anterior sides of the superior and inferior prostheses 10, 20, and positioning members 80 are provided for simultaneous insertion into the slots 84 of the superior and inferior prostheses 10, 20 so that the superior and inferior prostheses 10, 20 remain relatively fixed. Specifically, the slot 84 on the upper prosthesis 10 and the slot 84 on the lower prosthesis 20 are each rectangular slots 84 penetrating the inside, and the positioning member 80 is configured in an i-shaped structure, i.e., the positioning member 80 has two opposite insertion portions 81 and a connecting portion 82 interposed between the two insertion portions 81. As shown in fig. 4, the distance between the upper prosthesis 10 and the lower prosthesis 20 is adjusted to a minimum by screwing the screw 74 (i.e., the thickness of the intervertebral prosthesis is reduced to H1) before the intervertebral prosthesis is implanted between the vertebrae, and then the positioning members 80 are inserted into the two insertion slots 84, so that the distance between the upper prosthesis 10 and the lower prosthesis 20 is defined, and the two prostheses are maintained in a relatively fixed state. In this way, the intervertebral prosthesis can be implanted between vertebrae in a stable state with a minimum thickness.
In some preferred embodiments, the positioning member 80 includes two symmetrically arranged insertion holes 83 formed on the positioning member 80, so that the forceps can be inserted into the two insertion holes 83 through the head to clamp the intervertebral prosthesis, thereby facilitating the implantation operation of the forceps, and after the intervertebral prosthesis is implanted between the vertebrae, the positioning member 80 can be carried out by the forceps, thereby releasing the restriction of the positioning member 80 on the upper prosthesis 10 and the lower prosthesis 20.
The method of use and function of the above-described intervertebral prosthesis are described below.
First, as shown in fig. 4, before the intervertebral prosthesis is implanted into the intervertebral, the distance between the upper prosthesis 10 and the lower prosthesis 20 is adjusted to the minimum (the thickness of the intervertebral prosthesis is reduced to H1), and then the positioning member 80 is inserted into the insertion slot 84 to position the upper prosthesis 10 and the lower prosthesis 20.
The intervertebral prosthesis is then implanted between the vertebrae using the forceps and the positioning member 80 is then brought out, the upper prosthesis 10 and the lower prosthesis 20 being released.
The screw 74 is screwed by an operating tool such as a screwdriver to slide the movable receiving portion 42 toward the fixed receiving portion 41, thereby increasing the depth of insertion of the wedge pieces 60 between each other, thereby increasing the height of the stacked wedge pieces 60, as shown in fig. 5, thereby increasing the height between the upper prosthesis 10 and the lower prosthesis 20 (increasing the thickness of the intervertebral prosthesis to H2) to force the vertebrae to increase the intervertebral space. In the implantation operation, the excessive intervertebral space is prevented from being increased so as to avoid influencing the morphology of other vertebrae and surrounding tissues.
After the intervertebral prosthesis is implanted between the vertebrae, the springs 441 and the wave plates 45 serve to cushion the impact that the spinal motion may have on the intervertebral prosthesis, and the spherical portions 431 of the supporting members 43 cooperate with the upper prosthesis 10 to provide the intervertebral prosthesis with a degree of freedom. Thus, the intervertebral prosthesis is able to simulate the real joint to a great extent.
After the intervertebral prosthesis is implanted between the vertebrae, the reaction force of the spring 441 to the upper prosthesis 10 keeps the intervertebral prosthesis always in a trend of increasing thickness during the period in which the intervertebral prosthesis is not actively adjusted, which enables the intervertebral prosthesis to continuously expand the upper vertebrae 100, and the expansion process is slower, which not only reduces the influence on other vertebral forms, but also provides for the next active adjustment.
After a period of implantation of the intervertebral prosthesis, the screw 74 is again screwed to increase the thickness of the intervertebral prosthesis, thereby again actively increasing the intervertebral space, which is maximized to a physiological distance by actively increasing the thickness of the intervertebral prosthesis a plurality of times.
The key advantages of the intervertebral prosthesis provided by the invention are at least that:
1. the wedge-shaped sheets 60 of the two stacked assemblies have a friction self-locking function after being inserted between each other, so that the stacked assemblies can be stably maintained at the adjusted height, thereby enabling the intervertebral prosthesis to be stably maintained at the adjusted thickness.
2. The slope of the inclined surface of the wedge 60 is smaller, so that the distance that the wedge 60 and the movable receiving portion 42 need to move per unit height is larger, and the angle that the screw 74 needs to be screwed is larger, and thus the intervertebral prosthesis provided by the invention is more suitable for fine adjustment of the intervertebral space.
3. The cooperation of the mandrel 44, the spring 441 and the support member 43 keeps the intervertebral prosthesis of the invention always in a thicker trend, which allows the intervertebral prosthesis to continue to expand the superior vertebra 100, and this expansion process is slower, which not only reduces the impact on other vertebral forms, but also provides for the next active adjustment.
4. The wedge blocks are connected in a sliding mode through a dovetail structure, so that reciprocating linkage can be formed between the wedge blocks, and the thickness of the intervertebral prosthesis can be adjusted from large to small.
The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, the scope of which is defined by the claims. Various modifications and equivalent arrangements of this invention will occur to those skilled in the art, and are intended to be within the spirit and scope of the invention.
Claims (6)
1. An intervertebral prosthesis, comprising:
a lower prosthesis, the base of which is for fusion with the lower vertebrae;
an upper prosthesis, the top of which is for fusion with an upper vertebra;
an adjustment mechanism interposed between the upper prosthesis and the lower prosthesis;
the adjustment mechanism includes:
the fixing and accommodating parts comprise two fixing and accommodating parts which are symmetrically arranged on the lower prosthesis and are fixed with the lower prosthesis;
the movable containing parts are positioned between the two fixed containing parts and are symmetrically arranged, and the two movable containing parts face the two fixed containing parts respectively;
the driving mechanism is used for driving the two movable containing parts to synchronously and correspondingly move towards the two fixed containing parts or away from the fixed containing parts;
a first stacked assembly disposed in the fixed housing, the first stacked assembly including a plurality of wedge-shaped pieces stacked one on another with thin ends of the plurality of wedge-shaped pieces facing the movable housing;
a second stacked assembly disposed in the movable housing, the second stacked assembly including a plurality of wedge-shaped pieces stacked one on another with thin ends of the plurality of wedge-shaped pieces facing the fixed housing; wherein:
the wedge-shaped sheets of the second stacked assembly and the wedge-shaped sheets of the first stacked assembly are inserted into gaps among sheets, the driving mechanism drives the movable accommodating part to adjust the depth of the inserted wedge-shaped sheets to adjust the height formed by the stacked wedge-shaped sheets, and the upper prosthesis is adapted to the height change of the stacked wedge-shaped sheets;
a supporting component is arranged between the wedge-shaped piece on the uppermost layer and the lower prosthesis; the supporting part is provided with side wings formed on two sides and a spherical surface part which is positioned in the middle and protrudes upwards; the two side wings of the supporting part are respectively lapped on the wedge-shaped sheets at the two sides, and the spherical surface part is used for being matched with the middle part of the upper prosthesis;
the driving mechanism includes:
the first wedge-shaped blocks comprise two first wedge-shaped blocks which are symmetrically formed on the two movable accommodating parts respectively;
a second wedge block located between the two first wedge blocks, the second wedge block comprising a front second wedge block and a rear second wedge block; the front second wedge block and the rear second wedge block are matched with the inclined planes of the first wedge blocks at two sides and are in sliding connection with the dovetail guide strip through the dovetail groove;
the screw rod penetrates through the front second wedge block and the rear second wedge block to form threaded transmission, a force application part is formed at the end part of the screw rod, and the screw rod is screwed by the force application part to enable the front second wedge block and the rear second wedge block to be close to or far away from each other so as to drive the two first wedge blocks and the movable accommodating part to be far away from or close to each other;
a mandrel is arranged in the middle of the lower prosthesis, and the upper part of the mandrel passes through the center of the supporting part; the mandrel is provided with a step part, a spring is sleeved on the mandrel, and the spring is arranged between the step part and the supporting part; the screw rod radially penetrates through the bottom of the mandrel;
the intervertebral prosthesis further comprises a positioning component; slots are formed in the corresponding positions of the front side of the upper prosthesis and the front side of the lower prosthesis; the positioning component comprises a plug-in part which is matched with the slots of the upper prosthesis and the lower prosthesis respectively and a connecting part which is used for connecting the two plug-in parts; the positioning component is inserted into the slot through the inserting part to position the upper prosthesis and the lower prosthesis; the outer side of the positioning component is provided with an operation hole which is suitable for clamping an implantation operation workpiece;
a wave plate is arranged between the flank of the supporting part and the wedge-shaped piece at the uppermost layer.
2. An intervertebral prosthesis according to claim 1, wherein,
a first guide column is arranged in the fixed accommodating part; the wedge-shaped sheet of the first stacked assembly is provided with a guide hole, and the first guide column penetrates through the guide hole of the wedge-shaped sheet of the first stacked assembly;
a second guide column is arranged in the movable accommodating part; the wedge-shaped sheet of the second stacked assembly is provided with a guide hole, and the second guide column penetrates through the guide hole of the wedge-shaped sheet of the second stacked assembly.
3. The intervertebral prosthesis of claim 1, wherein the fixation receiving portion has two opposing inner side walls; the first stack being defined between two of the inner side walls; the movable housing having two opposing outer side walls, the second stack being defined between the two outer side walls; wherein:
the two outer side walls are correspondingly positioned outside the two inner side walls; the outer side wall and the inner side wall form sliding fit with the sliding groove through a sliding strip.
4. The intervertebral prosthesis of claim 1, wherein each of the wedge-shaped pieces has an outwardly protruding semicircular portion on both sides of the thick end; the cavity walls in the fixed accommodating part and the movable accommodating part are respectively provided with a semicircular groove matched with the semicircular part.
5. The intervertebral prosthesis according to claim 1, wherein two of the fixation receiving portions are provided with a limit cap; the middle part of the limit cover is provided with a hollowed-out part; the spherical surface part of the supporting part penetrates through the hollowed-out part.
6. An intervertebral prosthesis according to claim 2, wherein the positioning member comprises two symmetrically arranged.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310237426.8A CN115919515B (en) | 2023-03-14 | 2023-03-14 | Intervertebral prosthesis |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310237426.8A CN115919515B (en) | 2023-03-14 | 2023-03-14 | Intervertebral prosthesis |
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| CN115919515B true CN115919515B (en) | 2023-05-26 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111134913A (en) * | 2020-01-23 | 2020-05-12 | 北京爱康宜诚医疗器材有限公司 | Intervertebral fusion device |
| CN213190333U (en) * | 2020-06-10 | 2021-05-14 | 北京大学第三医院（北京大学第三临床医学院） | Distractable intervertebral fusion device |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4323034C1 (en) * | 1993-07-09 | 1994-07-28 | Lutz Biedermann | Placeholders, especially for an intervertebral disc |
| US20090005874A1 (en) * | 2003-04-22 | 2009-01-01 | Fleischmann Lewis W | Compressible, rotatable, and tiltable hydraulic spinal disc prosthesis system with selectable modular components |
| US7309363B2 (en) * | 2004-11-24 | 2007-12-18 | Depuy Products, Inc. | Adjustable knee tibial trial insert |
| US7799080B2 (en) * | 2005-04-22 | 2010-09-21 | Doty Keith L | Spinal disc prosthesis and methods of use |
| CN208243665U (en) * | 2017-07-17 | 2018-12-18 | 博能华医疗器械（北京）有限公司 | One kind can strut type Invasive lumbar fusion device |
| WO2019169036A1 (en) * | 2018-02-27 | 2019-09-06 | Life Spine, Inc. | Height adjustable spine implant |
| CN108515104A (en) * | 2018-05-21 | 2018-09-11 | 杨光明 | Adjustable cushion block |
| CN114533350A (en) * | 2022-01-27 | 2022-05-27 | 北京大学第三医院（北京大学第三临床医学院） | Artificial intervertebral disc prosthesis |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111134913A (en) * | 2020-01-23 | 2020-05-12 | 北京爱康宜诚医疗器材有限公司 | Intervertebral fusion device |
| CN213190333U (en) * | 2020-06-10 | 2021-05-14 | 北京大学第三医院（北京大学第三临床医学院） | Distractable intervertebral fusion device |
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